Method of and apparatus for producing pulp articles



g- 1943- V M. P. CHAPLIN ET AL 2,326,758

I METHOD OF AND APPARATUS FOR PRODUCING PULP ARTICLES Filed Oct. 26,1937 4 Sheets-Sheet 1 Aug. 17, 1943. M. P. CHAPLKN ET AL METHOD OF ANDAPPARATUS FOR PRODUCING PULP ARTICLES Filed Oct. 26, 1937 4 Sheets-Sheet2 Aug. 17, 1943. M. P. CHAPLIN ET AL METHOD OF AND APPARATUS FORPRODUCING PULP ARTICLES Filed Oct. 26, 1957 I 4 Sheets-Sizeet 5aw/esfaap/lh,

my M WWW Aug. 17, 1943. M. P. CHAPLIN ET AL 2,326,758

METHOD OF AND APPARATUS FOR PRODUCING PULP ARTICLES,

Filed Oct. 26, 1937 4 Sheets-Sheet 4 gin/woman;

Patented Aug. 17, 1943 METHOD OF AND APPARATUS FOR PRODUCING PULPARTICLES Merle P. Chaplin and Charles J. Chaplin, Portland, Maine,assignors to Chaplin Corporation, Portland, Maine, a corporation ofMaine Application October 26, 1937, Serial No. 171,156 A Claims. (Cl.9256) This invention relates to the moulding and forming of variousarticles from pulp, and more particularly to methods of and apparatusfor producing such articles.

For purposes of illustration, a method and ap- 5 intended. Further, acone structure made up of paratus are described herein, which areparticua soft material, does not have the necessary larly adapted to theproduction of textile cones, strength and rigidity to properly supportthe or cops such as are used in the textile industry thread or yarn whenthe cone is removed from for storing or transferring thread and yarnfrom the winding arbor. one machine to another, and for other purposes.Another expedient of the prior art is to make These cones or cops areusually made slightly tathe cone of astrong, hard material wound up inpering to enable them to be placed on mandrels layers, with an adhesiveto secure the layers toor arbors, both for winding and unwindingpurgether and to stiffen the cone'structure, the enposes, tirestructure-being placed in an oven to dry and It will be understood, inthe following descripharden the adhesive. After drying,such cone istion, that reference is made to textile cones or placed on an arbor andits surface abraded, cops simply by way of illustration, as both theground and brushed up to raise a nap of fibers method and apparatusherein described are well on its surfa t by p uc a'surface which adaptedto production of a wide range of prodwill assist in retaining the threador yarn in poucts, and hence the illustrations given herein are sition.The tip or small end of the cone is then not to be construed as limitingthe inventionto softened and rounded or burnished by a special t xtilecone operation which includes the application of hard- In themanufacture of articles of this nature ening and stiffening materialseffective to promany considerations arise; it is necessary that duce thenecessary hardness and smoothness in the article be light in weight,uniform in thickthe finished tip. v ness and size, and be reasonablystrong and stiff Diii'iculties have been experienced with such so thatin use, when the cone or cop is removed D laminated articles, which areusually made from from its arbor after being wound, it will hold thepaper wound and held together by adhesives, e. g., thread or yarnthereon firmly and without danger since the tip of the cone is reshapedor reformed of becoming loosened, due to collapse or shrinkby burnishingit is almost impossible to mainage of the cone itself. tain same in itsnew shape. The cone as orig- It is also desirable, along with strengthand inally wound fromipaper has a straight uniform rigidity, to have atleast a portion of the surface taper, but in rounding the uniform tip asis of certain types of cone velvety in texture, that necessary tofacilitateremoval or unwinding of is relatively soft and yielding toprovide a surthe threads or yarns, the paper material of the face whichthe first layers of thread or yarn may cone is distorted, bent andgenerally disrupted. grip, whereby to obviate any danger of looseningHence the material has a greater tendency to reby downward slippage onthe taper of the cone. turn to its original condition, particularlydueto In unwinding the thread or yarn on convendampness or otherunfavorable conditionsunder' tional machinery, the strands are drawnover 40 which the cones may be stored or used. the small end of thecone, and during the lat- Th Cones, as t t are usually"fbrmed e P Ofunwinding c in ih tapered sections, and the makeup of the article up ofthe cone. ThlS tip, after continued use is from sheets-of paper not onlyinvolves expensive apt becolPe Worn and ne Fhereby operations,use ofadhesives, etc., but what is-even I tg g i g g gigg g z ai g 2%: moreobjectionable, there-is a verylarge waste a 6 1p 0 of material, becausethe cone cannot be wound cone be smooth and hard and have a surface f tht d d h t b t t be F which will resist abrasion or roughening due to mm5 mg 6 ge ee u 1 W0 contact with the thread of the yarn during such mf h4* on clrcle P t all of unwindmg procesa tenal. outside of theparticular shape of 'sheet Previous expedients have been either to make15 Wastethe cone structure of a soft material, with rein- D 9 p jctlces, and the various operaforcements of metal or other hard materialat tlons entermg Int-0 the ll p of cone such portions of the conesurface as are subject S r cture as described are slow and expensive, towear. This is undesirable, both from a cost standpoint and from astructural standpoint,

since the reinforcing material is apt to become loosened from the mainbody of the cone thereby defeating the very purposes for whichit is andfall short of providing an ideal structure.

even after all the additional work and processes have been performed.

Accordingly, it is a primary object of the present invention to producean article which not only meets requirements but which is also ofgreater utility than any article of this nature at present available.

It is another and important object of this invention to provide such anarticle by a. method which eliminates many expensive operationsheretofore found necessary.

Still a further object contemplates the use of simplified apparatus aone mode of carrying out the method and which apparatus is particularlyadaptable to production of an article having the characteristics setforth.

The article produced by the method and apparatus of this invention ismade of pulp, integrally moulded and finished in a series of automaticoperations, to the exact shape and size required by the finishedarticle, thereby eliminating all waste of material. It has incorporatedin it, as a unitary structure, pulp materials on the inside which makean article that is hard, stiif, rigid and strong, while at the same timea certain portion of the outer surface is made up of a softer fibrousmaterial which, in the finished article, is integral with the hard, tillstructure, thus providing the necessary character of surface forretaining the thread in place, regardless of taper. The tip or end ofthe cone is molded and finished to the exact required shape and itssurface is integral with the remainder of the surface, but the pulpmaterial which renders this portion of the article is of a nature tofurnish a smooth hard surface. The entire cone structure being thusmoulded and finished as an integral unitary article havin incorporatedtherein pulp materials fulfilling the requirements of use as regardsstrength and character of the surface at different parts, greatlyreduces the cost of manufacture and overcomes many of the objections tothe present articles made up from sheets of paper.

All of the objections to prior art practices and structures are overcomein the article, method and apparatus, e. g., any deformation or changein the shape of the tip is avoided as the article is integrally mouldedin its final position 'and there is no tendency of the fibers in anypart of the cone structure to change position, due to the integral,moulding to a final fixed position; waste is avoided, extra operationseliminated, and time and labor minimized, all of which reduces the cost.

In a copending application. Ser. No. 171,155

showing the first step of the method;

Fig. 2 is a section on the line 22 of Fig. 1;

Fig. 3 is a secticn of the first and second primary moulding dies,illustrating the second step of the method;

Fig. 4 is a section of the first and third moulding dies, illustratinthe third step of the method;

Fig. 5 is a section on the line 55 of Fig. 4;

Fig. 6 is a section of another die arrangement, illustrating the fourthstep of the method;

Fig. '7 is a section through a pair of finishing dies illustrating afinal step of the method;

Fig. 8 is a section on the line 88 of Fig. 7;

Fig. 9 is an enlarged fragmentary detail of Fig. 8;

Fig. 10 is a section of an assembled cone prior to consolidation andfinishing;

Fig. 11 is an end view of the cone in Fig. 10;

Fig. 12 is a section through a finished cone;

Fig. 13 is an end view thereof Fig..14 is a side elevation of a slightlymodified, finished cone; and

Fig. 15 is an end view thereof.

Referring now more particularly to the drawings in which like referencenumerals designate like parts, it will be observed that the method,generally, consists in building up and assembling sections of pulp onsets of moulding dies, and thereafter compacting and integrating saidsec tions to consolidate them into a single integral structure.

The method by which such a cone structure is built up and assembled isillustrated in Figs. 1 to 6, in which Fig. 1 shows a primary moulding,or inside, male forming die A provided with a hollow, tapered dieportion having an internal chamber 2|, the walls of which are perforatedas indicated at 22. Encompassing the exterior of the die is a formingscreen 23 for receiving a pulp deposit, this screen being held in placeby a clamping ring 24 at one end of the die and by a threaded plug 25 atthe tip end. The plug 25 has the dual purpose of securing the screen 23in place and defining the end of the moulded pulp sheet which will beformed upon the die. This plug includes a centering tip 26 cooperativewith mating dies hereinafter described.

The screen 23 will be made up from a sheet of suitable size, formed toappropriate shape with overlapping edges at the seam or joint, whichedges are tucked through the slot 21 cut in the side of the die.

After the screen has been formed in proper shape, and prior to placementover the tapered portion 20 of the die, the folded in edges thereof aretemporarily secured together and the entire screen is given a heavyelectroplating of copper, nickel, or other suitable material, renderingit stiff and sturdy so that when it is installed upon the member 20, thefolded edges may be tucked into the slot 21 to firmly secure the screenin place, and thus eliminate any joints over which it might b difficultto deposit a layer of pulp. The screen desirably will be electroplatedin such a way as to accentuate the corrugations of the formed wire onthe inside of the screen, i. e., next to the member 20, to facilitatedrainage between the wire or screen and the member 2|], prior to passageof such drainage through the holes or perforations 22 into the chamber2|. The outside of the screen, however, will desirably be plated in sucha manner as to render it as smooth as possible, and this smoothness maybe enhanced by polishing the outside surface after plating.

The electroplating not only serves to stiffen and strengthen the screenbut permits the outer surface to be made as smooth as possible withoutweakening the screen structure. Furthermore, a coarser mesh screen maybe used initially than would otherwise seem to be de irable since theplating serves to close up the mesh somewhat, rendering it in bettercondition for pulp deposition and formation.

A plunger-like cover 28 having a suction or pressure line 29 leading tothe interior of the die serves to complete the assembly of the primarymoulding or forming die.

A female moulding or intermediate forming die B is illustrated in Fig.3, and comprises an outer casing 30 and an inner form 3|, the space 32between the casing and inner form serving as a vacuum and pressurechamber 32. The perforations 33 serve to establish communication betweenthe chamber 32 and the interior of the form or die portion 3|. A pulpforming screen 34 lining the form member 3|, is secured in position atthe base'of the die between a flange 35 at the base of the form portionand a clamping plate 36. This wire mesh or screen surface is made up ina manner similar to that described in connection with the screen 23 withthe exception, of course, that the mesh is secured at its joint bybending the edges outwardly instead of inwardly through a slot 21extending along the die 3| It is not necessary to secure the end of thescreen in place at the innermost end portion of the die 3| since theelectroplating stiffening will render the screen sufficiently rigid tofix it in place.

A slidable plunger 39 is mounted at the inner end of the die portion 3|,and extends completely therethrough, fitting closely inside of theforming wire. internal diameter efiective toclosely fit or engage thetip end 26 of the plug 25 in the die 20.

The plunger 39 has a stem 4| encircled by a spring 42, and extendingoutwardly through the casing 30, the spring 42 bearing against the innerside of the casing 30 and a flange 43 on the plunger 39. With thisarrangement, when the die A is inserted in the die member B in a mannerhereinafter described, the two dies will be rela- This plunger isrecessed, as at 40, to an I will further be apparent that a series ofmale dies tively centered and a proper fit will be insured forassembling the moulded layers of pulp formed on these dies. V

Fig. 4 illustrates a female moulding or out-, side forming die C whichis in all respects similar to the die B except for a greater internaldiame ter; and the same reference numerals are applied thereto. Asuction or pressure line 44 completes the assemblage of the forming diesB and C.

Fig. 6 illustrates a female moulding oroutside forming die D which issimilar in all respects to the dies B and C, except that thelongitudinal dimension thereof is considerabl less. The die includes acasing 45-, an internal orming die portion 46, a foraminous screenor-mesh 41, a plung- 7 er 48 having a stem 49 surrounded by a spring 50,all functioning as in the case of the outside forming dies of Figs. 3and 4, perforations 5|. serving to establish communication through thedie portion 46, and a suction line 52 extending from the interior ofthe'chamber' 53 formed inside of the casing 45. The purpose of this dieis to form short tip portions for the pulp articles.

The dies thus far described are well adapted to the formation of thecomponent portions or sections of the article and to the assemblage ofsuch portions, as they are formed, into a composite whole. While fourforming dies have been described, it will be obvious that this number issusceptible to variations, dependentv upon charsimilar to die A exceptfor size, might be used as intermediate forming dies in lieu of thefemale die assemblage B.

After assemblage of the component parts or sections of the article,transfer may be made to a set of finishing dies, for ultimate compactingand consolidation ,into the integral final product. Fig. 7 illustratestwo finishing dies, of which an inside die E mates with an outsidefinishing die F. Both of these dies are provided with heat for theevaporation of any moisture left in the moulded article and for theaccurate finishing of both inside and outside surfaces. The die E isformed with a tip having one diameter 54 to fit an opening in the die F,and another diameter at 55, enabling cooperation with the forming die D,when the pulp is transferred. The die E also will be groovedlongitudinally as at 55, along its surface, and will be perforated, asat 51, to establish communication with an inner vacuum chamber 58, butthe internal surfaces of the die F preferably will be smooth.

In a copending application,'Ser. No. 171,157 filed of even dateherewith, an apparatus including formingand finishing dies, and the modeof making same is described and claimed, such apparatus beingparticularly adapted to the purposes herein set forth.

The production of certain articles of the nature contemplated herein canfrequently be most economically produced by moulding them to theapproximately desired shape from a liquid pulp mixture, and dies A, B, Cand D lend themselves most readily to such mofilding. These ,articlesafter being moulded may be subsequently dried, and in some cases arefinished by being compressed between smooth and heated dies of which thedies E and F are examples.

With ordinary pulp moulding methods, where the pulp fibers are depositedon a foraminous die by suction, the fibers collect rapidly and compactlyuntil a certain thickness of deposit is attained over the die, afterwhich deposit is relatively small, or ceases altogether. During thelatter part of this deposit the fibers are not compacted as firmlytogether as initially, and any extra thick moulded pulp article or sheetdoes not have the density, hardness or strength throughout as issometimes necessary for particular conditions andresults.

Where, as in the present instance, it is desired to provide a strong,dense wall. in the moulded pulp structure, which wall is both thickerand stronger than ordinary methods and apparatus will produce,-specialmeans are necessary to secure the desired result. It is for this reasonthat the series of forming or moulding dies A, B, C and D are provided,and upon which separate portion of the completed article may .be formed,for subsequent consolidation. The

A method of building the cone structure, by

use ofthe apparatus described above is as follows:

First, a section 59 of pulp of suitable density and compactness to give,in the finished article, a hardrigid body, is deposited'upon theexterior of the screen 23 of the foraminous die A, suction being appliedthrough the line 29 to the chamber 2| to remove excess liquid from thepulp layer 59, through the perforations 22.

The deposit is not permitted to build up to a thickness where theoutermost fibers are loosely deposited or improperly felted because ofloss of suction which will necessarily occur as the thickness increases.It will be understood that this deposit is of a character effective toprovide the necessary hardness and rigidity required in the finishedarticle.

It also will be readily understood that the vacuum or suction behind orwithin a foraminous moulding die and a screen results in a correspondingpressure being applied on the outside of the moulding screen, either tothe liquid passing through or to the fibers retained on the screen, orto the complete fiber deposit on the screen after it has been removedfrom its original liquid mixture.

Similarly, a section 80 of pulp having the proper constituency isdeposited on the screen 34, internally of die B. The die A with itssection 59 is then inserted into the portion 3|, being centered by theclamping ring 24 and the plug 26, which latter is yieldingly received bythe plunger 39, until the sections 59 and 60 are in nested contact, andin substantially adhering relation to each other. At this time thesuction in chamber 32 is replaced by air under pressure, forced into thechamber through the line 44 (not shown in this figure). Suction ismaintained in the meantime in the chamber 2| of die A, whereupon the dieA may be removed with both sections of pulp 59 and 60 supported thereon.

Meanwhile, a section SI of pulp will be formed or deposited on thescreen 34 of a forming die C, the deposition being effected as in thecase of the dies A and B. This die, as stated, may be identical with dieB, except that its internal diameter is slightly larger to accommodatesections 59 and 60, as well as 6|. The section of pulp BI is slightlydifierent in consistency, from that of the sections 59 and 60, sincethis section is to provide the exterior surface of the finished articleand must present a surface of sufiicient softness and velvety texture asto retain in position, threads or yarns which may be wound upon the conewhen finished, without however abrading or harming them. After thisouter or surface section is moulded or formed in the die C, the die Awith its two sections may be inserted therein, to nest the threesections. As soon as the sections have been compacted together, pressureinstead of suction is applied to the chamber 2| of die A, suction beingmaintained in the chamber 32-of die C and the die A is then removed fromthe pulp sections. The finishing die E is now inserted in place of thedie A and by reversal of pressure and suction, may be removed from theinterior of die C, with the three sections mounted thereon.

A compact, dense section 62 of pulp which will dry into a hard sectionis deposited upon the screen 41 of forming die D, and thereafter thefinishing die E with its three sections is inserted as shown in Fig. 6.By suitable application of pressure from the chamber 53, the finishingdie may be removed with this fourth section compressed upon the tip end.of the three sections 59, 60 and 6|. The finishing die E is theninserted into a mating, hollow finishing die F and all sectionscompacted and smoothed into a single compact, integral structure, suchthat there is no single, section which is separate from remainingcomponent portions of the structure.

This operation has the effect of forcing the harder tip section 62 intoa smooth surface relation withthe major portion of the softer section6|, and because of the added compression between the sections 62 and 6|at the tip, the tip end of the resultant article will be even more denseand compact than the remainder of the article. Both finishing dies E andF are heated by suitable means, not shown, to cause evaporation of anywater remaining in the moulded pulp, this water being drawn off orescaping in the form of vapor through the central chamber or opening 58and perforations 51, as well as through the slots which extendlongitudinally of the die E between perforations. By reference to Fig.9, it will be seen that the slots 55 are of suilicient depth to providea drainage passage under the pulp.

From the foregoing, it will be observed that a moulded cone may be madeup of a plurality of separately moulded sections, assembled, compactedtogether and finished as an integral article. A hard stifi portion hasbeen formed as two pieces, i. e., sections 59 and 60, with a softsurface portion 6|, and a hard tip portion 62. After the several dense,compact sections or portions have been formed separately, they are thenfinally assembled and intergratedbetween the finishing dies E and F,which are heated to evaporate any moisture left in the moulded article,and to accurately finish both inside and outside surfaces of the mouldedcone, in addition to consolidating all portions or sections into asingle homogeneous unit.

By virtue of the grooves 56 arranged longitudinally of the exterior ofthe die E, small ribs or projections 53 will be formed on the interiorof the moulded cone, for the purpose of forming a. seat to grip adriving arbor upon which the cone will be mounted when in use, but thesegrooves 55, as stated above, are of such a depth that the formed ribs orprojections will not completely occupy the grooves and thus a passage isleft for drainage purposes.

If it is found for some uses that the rib or ridge portions 63 areundesirable, then they may be eliminated during the finishing operationsby partially drying the article in one position, separating the dies Eand F slightly and turning the die E to bring the smooth surfaces of thedie over the ridges on the article. Subsequent pressure upon the articlebetween the two dies will then smooth out the ridges and complete themoisture evaporation.

A finished, moulded pulp article, made as described above, appears inFigures 12 and 13. This article, illustrated as a cone or cop M, has asurface which is soft and velvety in nature, except for the tip portionwhich is, of course, very hard and rigid, and the soft surface isdesirable for use with finer and more delicate threads or yarn whichmust be prevented from slipping down over a cone surface, but which willnot stand being wound upon a rough or serrated surface.

Coarser threads or yarns may require a rough or semi-rough type ofsurface, as contrasted with that shown exteriorly of the cone in Fig.12, and such a surface, in prior practice, is made by running thematerial of the cone over corrugated rollers or by corrugating the conesurface after the cone is formed.

A modified type of moulded cone is shown in Figs. 14 and 15, which mayreadily be made by the method and with the apparatus of the presentinvention, such modification being a cone M moulded with smallprojections 65 substantially parallel to the axis of the cone, andproduced by milled recesses in the exterior finishing die F.

The foregoing embodiments are, of course, but illustrative andmodification may be made further without departing from the spirit ofthis invention. Such modification might include the production of astraight tube, or a tube having a straight cylindrical portion with atapered base or end portion. So far as is known, no methods or apparatusare at present available for moulding a tube, cylinder or cone except bmeans of a split die and one of the inherent advantages of the presentconstruction is the elimination of split dies.

Even with split dies, there is no method of forming cones or tubes ofthis general nature with a central hole of uniform diameterthroughoutits length, such as is possible by the present method and apparatus.

While the method and apparatus have been described particularly withreference to tubular tapered articles, such as a textile cone or cop, itwill be readily understood that such description is intended asillustrative rather than limiting, since both the method and apparatusare readily applicable to the production of a wide range of articles,and can be used to produce other types of tubular and non-tubulararticles, such as boxes, loud speaker cones, egg-flats, etc. The rangeof use of the invention is almost unlimited and, accordingly, theinvention herein is not to be limited in scope, other than defined inthe appended claims.

Having thus described our invention, what we claim as new and desire tosecure by Letters Patent of the United States is:

1. The method of moulding fibrous pulp articles which comprisesseparately forming a plurality of tubular fibrous pulp sections ofrelatively varying hardness and compactness, assembling and compactingsame in nested relation while in a moist condition to unite them withthe hardest, most compact section internally of the assemblage and thesoftest section externally thereof, forming a tip section of a hardnessand compactness comparable to the hardest of said tubular sections, andof a diameter approximating that of the softest section, assembling sameexternally of one end of the said nested sections, and thereafterseparately finishing the assemblage from a moist condition by furthercompacting, and consolidating all sections into a single non-laminatedintegral structure.

2. The method of moulding tubular fibrous pulp articles which comprisesforming a hard compact tube of moulded pulp fibers, forming another tubeof moulded pulp fibers with a relatively softer outer surface, nestingsaid tubes while moist with said soft surface exteriorly of theassemblage, forming a short relatively hard tube of lesser length thansaid first mentioned tubes, and of a diameter approximating that Ofsaidsoft surfaced tube, each of said tubes being formed separately ondifferent molding dies, assembling said soft short tube exteriorly ofthe assemblage of longer tubes while moist, and further compacting andintegrating the complete assemblage from a moist condition as a separateoperation under heat and pressure efiective to thoroughly dry andconsolidate said tubes into a single non-laminated integral structure.

3. The method of producing a fibrous pulp article of the class describedwhich comprises moulding on a foraminous die contoured to theapproximate shape of the desired article, a thin relatively densecompact conical tube, of forming on a second contoured die a thincompact conical shaped tube of lesser compactness than said first tubecontoured to overlie and fit the dense tube formed on the firstmentioned die, of forming on said tubes, as a separate operation, innested relation to each other while moist, and of holding said tubes incompact condition until water or other liquid contained therein has beenremoved.

4. An apparatus for moulding fibrous pulp articles comprising acontoured spindledike foraminous inside forming die adapted to receive afibrous pulp deposit over its external surface, a hollow contouredforaminous intermediate forming die adapted to receive a fibrous pulpdeposit over its internal surface, and a hollow contoured foraminousoutside forming die adapted to receive a fibrous pulp deposit over itsinternal surface, said dies being arranged to separately mould pulpsections for nesting, assembling and uniting upon said inside formingdie, means for transferring an assemblage of sections from one die toanother; finishing dies for separately compacting, drying andconsolidating the assemblage of formed sections into a single unitarynon-laminated structure, and means for transferring said assemblage fromthe forming dies to the finishing dies.

5. An apparatus for moulding fibrous pulp articles comprising acontoured inside forming die having a foraminous body and a formingscreen externally thereof for deposition of a section of fibrous pulp, acontoured outside forming die having a foraminous body and a-mouldingscreen internally thereof for a deposition of a section of fibrous pulp,a foraminous tip forming die having a moulding screen for deposition ofa tip section of fibrous pulp, said dies being correlated and adaptedfor assembly with deposited sections of pulp, one within the other, tounite the pulp depositions to each other, and for removal of thesections of pulp in assembled relation, from said dies, and with the tipsection externally of one end of the assemblage, and separate die meansupon which said assembled sections are finished into a single,non-laminated, integral structure.

MERLE P. CHAPLIN. CHARLES J. CHAPLIN.

